"Create a vegan Lavender Twix Bars recipe based on the provided ingredient list and details. Use imperial units. Include a caramelized shortbread base, lavender coconut ganache, and dark chocolate coating with a drizzle. The user asks whether purple carrot powder can be substituted with butterfly pea powder; include a brief note in the recipe or notes about that substitution and any color/flavor differences. Serves 12 medium bars, total time about 90 minutes."